﻿using System;
class variable
{
    public static void Main()
    {
        int radius = 4;
        const double pi = 3.14159;
        double circum,are;
        are = pi * radius * radius;
        circum = 2 * pi*radius;
        //in ket qua
        Console.WriteLine("bankinh={0},pi={1}",radius,pi);
        Console.WriteLine("dientich{0}",are);
        Console.WriteLine("Chuvi{0}",circum);

    }